多尺度调控Sb2Te3基材料的热电输运性能的研究

热电材料能够实现电能和热能的相互转换，引起广泛的研究。能带工程、载流子工程、声子工程是调控电热输运性能的重要途径。如何将多种手段协同利用，全面解除电热输运耦合关系是研究的重要方向。本研究通过对Sb2Te3进行掺杂，然后继续复合金属纳米粒子，从原子尺度、纳米尺度、介观尺度等多尺度调控Sb2Te3的热电性能。研究原子缺陷、纳米晶粒、微米晶界等多尺度结构对载流子传输特性和声子输运行为的影响规律。辅助正电子手段研究热电材料的缺陷对性能的影响规律，勾画出热电参数的耦合关系解除的物理图景，为进一步开展高性能热电材料的研究提供依据和指导。

Thermoelectric materials enable conversion between thermal and electrical energy, which has attached great attention. Band engineering, carrier engineering and phonon engineering are important approaches to improve thermoelectric property. How to decouple electrical and thermal property via synergetic way are significant research fields. In this project, we obtained all scale microstructures by doping Sb2Te3 at A or B sites and introducing metal materials. The influence of all scale microstructures (atomic defects、nanostructured grains and mesoscopic boundaries) were explored. Combining with the positron annihilation measurement, the physical mechanism of defects on thermoelectric property was revealed through analyzing the diffusion lifetime and intensity, The eventual purpose of the project is to provide guidance and directions for other thermoelectric materials.